Special Theory of Relativity

Most problems have moved to:

bullet http://electron9.phys.utk.edu/phys513/Modules/module_7.htm
bullet http://electron9.phys.utk.edu/phys513/Modules/module_8.htm

bulletProblem:

A fixed center of force at the origin repels a particle of mass m with a force whose magnitude is k/r2.  The particles kinetic energy at a large distance from the origin is E0 and may have values between 0 and ¥.  In the absence of a force the particle would move along the line given by y = 0, x = b.  With the assumed force, what will be the distance of closest approach, a, to the origin when the particle is treated relativistically?  Show that your result reduces to the obvious answer if k = 0, that a  =k/E0 for a head-on collision where b = 0 and that your result reduces to the nonrelativistic result when E0 << mc2.

bulletSolution:

bulletProblem:
A relativistic particle is launched at the origin (0,0) with initial momentum P(0) = (Px(0),Py(0)),  with Px(0) > 0 and Py(0) > 0, and is subject to a constant force pointing in the negative y direction.

(a)  Solve the equations of motion.
(b)  Determine the time T at which the particle reaches the x-axis again (i.e. y(T) = 0).
(c)  Find the trajectory of the particle, i.e. y = y(x).

NOTE: Give all answers for the laboratory frame.

bulletSolution:

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bulletProblem:
Consider a thin rod of length d and constant linear mass density s.  The rod is assumed to remain straight at all times, and to be unstretchable.  The rod is rotated about its center such that the endpoints moving tangentially at v ~ c.

 

Show that the total energy of the rod E and its angular momentum J are related by 

bulletSolution:

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